A novel class of CPM signals with high-bandwidth efficiency

Abstract

Continuous phase modulation (CPM) signals are attractive for their good power and spectral efficiency within the class of constant envelope signals, but the receiver complexity is usually too high. Among the complexity reduction approaches, the PAM representation of CPM, as Laurent's work is commonly known, has received a lot of attention due to its effectiveness and excellent BER performance. More recently, CPM signals with separable phase property was proved to have minimal cardinality among the existing pulse amplitude modulation (PAM) approaches. Despite reduction in the detection complexity, the bandwidth of the signals is poor for the higher slope in phase response function, which causes slower sidelobes decays. To overcome the drawback, we propose a new class of CPM with separable phase property. The new class of CPM are very close to the conventional CPM in bandwidth and power efficiency.